Foam suppressant for aqueous mixtures, e.g. cooling lubricants, polymer dispersions or paint, comprises N,N'-substituted urea derivatives in the form of solid particles made by crystallization from a dispersed melt

摘要

A foam suppressant for aqueous media comprises N,N'-substituted ureas in which the terminal substituents are 4-30C hydrocarbon residues (optionally with a carbonyl group) or 4-24C hydrocarbon residues with a nitrogen atom, used in the form of solid particles obtained by crystallization from a clear, homogeneous melt dispersed in a carrier. An anti-foaming agent for aqueous media contains urea derivatives of formula (I) in the form of solid particles obtained by crystallization from a clear homogeneous melt dispersed in a carrier medium. R<1> = 4-30C hydrocarbyl, nitrogen-containing 4-24C hydrocarbyl or 4-30C hydrocarbyl with a carbonyl group; R<2>, R<3> = H or 1-24C hydrocarbyl; R<4> = a 2-30C organic residue; n = 0-5.